Spading-plate for waterproof footwear.



K-. F. W. KOCH. SPADING PLATE FOR WATERPROOF FOOTWEAR APPLICATION F1L1ED.0CT.5..1914.

Patented Aug. 31, 1915.

arca es,

KARL F. W. KOCH, OF CHICAGO, ILLINOIS.

SPAlDING-PLATE FOR WATERPROOF FOOTWEAR.

Epecificatio ors Patent. Patented Amigo 31L, lfillfi,

Application filed October 5, 1914. Serial No. 364 969.

To all whom it may concern Be it lmown that I, KARL F. W. Koorr, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in Spading-Plates for Waterproof Footwear, of which the follow ing is a specification My invention relates to spading plates for Waterproof foot wear, and particularly'relates to a plate which may be applied to the under side of a waterproof boot or shoe to protect the same from abuse caused by the use of spades or shovels, or otherwise.

' Heretofore when doing heavy spading or shoveling in wet ground men havebeen in the habit of wearing heavy leather-soled rubber boots which, besides being very heavy and clumsy, have-been considerably more costly than ordinary rubber footwear.

lhere is at the pnese'nt time an increasing demand for bootsjwhich, besides being lighter, shall be much less expensive than,

the customary heavy leather-soled boot. Certain improved modern processes, such as the vacuum process, for the production of rubber goods have resulted in very great improvements in the wearing qualities of rubber boots, and. at the present time it would be quite feasibleto manufacture a rubber boot ,for the use of laborers operating spades and shovels ifit were not for the fact that the shank of the shoe is unable to stand up 'under the abuse of the spade or shovel when the foot is used to assist in the operation. I 011 this" account workmen either hesitate to employ the under side of the or- 'dinary boot to 'assist'inf such manipulation of the spade or shovel, thusoperating atreduced efficiency, or they still purchase the heavy leather-soled boots which, as before stated, are very expensive besides 7 being clumsy and hard on the feet. Some desultory' attemptshave been madeito apply protective plates to shoes, but, so far as l am aware, such attempts havebeen confined to ordinary boots and shoes and have re sulted in devices which have either rendered the boot heavy and clumsy or haveimpaired its waterproof properties.

tive metal plate is securely applied to the under side of a waterproof boot or shoe for the purpose of protecting the latter from injury; to, provide a construction of the class described in which the plate if desired may be applied only to that part ofv the shoe which receives the most wear and where it does not seriously if at all interfere with the flexible character of the sole; to provide a construction of the class described which re sults in practically no increase in weight over that of the, ordinary boot or shoe unprovided with such a protector; to provide a construction in which the said plate is securely attached to the shoe or boot without the use of extraneous fastenings, which might be liable to become broken or displaced or cause an accumulation of foreign matter; to provide a construction of the type referred to in which the metal plate is located entirely or almost entirely below the upper of the boot or shoe-so as not to interfere with the free movement of the foot inside the shoe or cause the upper portion of the shoe to present an unsightly appearance; to provide a construction in which the plate is securely united to the shoe bymeans of a member or members embedded in the rubber of the shoe during the process of manufacture so that the shoe loses none of the waterproof characteristics of ordinary rubber foot wear; to provide a construction in which the anchoring means for .the plate is integrally built into the shoe or boot during the process of forming the latter prior to vulcanization and afterward vulcanizing the assembly in its final posi-' lit) shall be simple and economical j m u 1" ture, and, in general, to provide an im if proved construction of the class'referredto.

In describing my inventi0n, I prefer to illustrate it by means of the accompanying drawings which show a practical embodiment of my invention as applied to a rubber boot of the type usually worn by welldig- *gers or sewer-excavators when working in wet ground.

The salient objects of my-invention are,fto provide a construction in which a protecview of the metal anchor plate, and Fig. is a plan view of a spading plate.

Referring to the drawings, designates as a whole a rubber boot to the under side of which my improved wear plate is applied, this boot being of the usual type built plurality of rivets or pins 12 which extend into the shank'of the'boot and are there united to an anchor plate 13. This anchor plate 13 is preferably incorporated into the shank of the shoe during the process of manufacture and in the following manner:

4 The first step in the process of building up i the bottom of the shoe upon the last consists in the application to the last of the prepared canvas insole 14. The operator then applies to the canvas insole in the reglon of the shank a sheet rubber packing piece 15 whichhas an area considerably greater 1 than that of the anchor plate 13. .The next step is to apply the anchor plate 13, to which the four rivets 12 have been previously united. It will be noticed that the vent longitudinal movement of' the rivets said rivets 12 where they enter the anchor plate 13 are considerably reduced in cross section so as to form shoulders, which prein'the anchor plate 13'while' the outer wear ency of the material of which said layers plate 11 is beingriveted in place. After the anchor plate 13 has'been placed in position, a second rubber sheet 16 is forced over it,

'this' rubber sheet being somewhat .longer than the rubber packing sheet 15 and substantially of thesame width. It should be noted that in applying the sheet 16 and the succeeding layers, holes are not previously formed to admit the rivets which make their own holes when the rubber orcanvas sheets areapplied. This insures a snug fit between the rivets and the layers through which they pass, due to the resiliare composed. After the second rubber sheet 16 has been placed in position the heel and sole of the shoe are built up to the same level as the shank by adding fillers 17, which fillers comprise layers of canvas or other fabric to which has been applied a coating or filling of rubber compound. It should be noted, however, that the rubber sheets inclosing the anchor plate 13 are made of a grade of rubber considerably higher than-that of the fillers 17. Having built up the under side of the shoe to a substantially equal thickness throughout its length, a second set of fillers 18 and 19 is applied prior to the attachment of the sole and heel 20 and 21. These latter are carried by a comparatively thin sheet 22, the outer edges of which extend for some distance beyond the outline of the sole and heel and are folded up over the lower edge of the upper 23, as shown. Although under some circumstances it might be desirable to defer the application of the wear plate 11 until vulcanization of the boot was effected. I prefer to apply the said plate and rivet it in'position before the shoe is vulcanized so that there is no possibility of injuring the partsof the completed shoe during the said riveting operation, and, in addition, because when the plate is riveted in position before vulcanizing the whole assembly is tightly squeezed together and becomes a coherent unitary structure during the vulcanizing process. In order to render the anchoring means 13 still more 'efiective I form therein a plurality of apertures 24 which are filled with a rubber compound during the process of building up the shoe. Thus, when the shoe is vulcanized, this compound becomes vulcanized and united to the rubber sheets on either side of the anchor plate 13, the

.outer margins of the said sheets 15 and 16 also becoming securely vulcanized together. I prefer to employ the vacuum process during the vulcanization of the shoe or boot, which process I have found secures an extremely dense and tough body of rubber at the same time reinforcingit substantially.

The plates 11 and 13 are preferably constructed of stiff sheet metal by means of suitable dies, andthe formation of the corrugations'in the under side of the plate 11 thus results in the formation of corresponding depressions 27 on the under side thereof into which the rubber of the shank is forced when the wear plate is riveted in position prior to vulcanization. This feature assists materially inpreventing longitudinal nrovement of the wear plate, without placing too much dependence upon the stiffness of the rivets 12. It should be noted also that the side edges of the spading plate 11 are flanged up to conform with and hug the-side of the shank, as shown at 28,- thus to a certain extent protecting the sides 'of the shank while at the same time assisting in the prevention of lateral movement of the spading plate.

Although I have shown a wear plate which is primarily adapted to prevent abuse caused by the use of a spade or shovel, it

will be obvious that the plate could be made considerably larger in. area so as to protect practically the entire area of the under side of thejboot, if founddesirable. It will also be apparent to those skilled in the art that my construction in no way impairs the waterproof quality of the boot owing to the mannerin which the parts are incorporated into the material of the boot, and this results in a simple, neat and economical construction which is particularly-well designed to carry out the purpose and fulfill the objects previously set forth.

It will be manifest to those skilled in the I art that although I have described what I consider to be'a preferred embodiment of the novel featuresof my invention, yet the details may be varied considerably without sacrificing any of the advantages or benefits thereof, and consequently I do not wish tobe limited in the use of my invention,'except as specified in-the appended claims.

I,cla11n..

l. The combinatiou'of an article of foot wear provided With a base'including a pair pound, of a horizontally disposed anchor plate inserted between said layers, prior to vulcanization of the base,-a connecting-member secured to and extending from-said anchor plate outwardly through the bottom layer, and an outer .plate secured to the lower end of said connecting member.

3. In rubber footwear, the combination with the base provided with two distinct superposed layers of. rubber compound, a horizontallydisposed anchor plate of extended area, provided with openings therein and inserted between said layers-prior to vulcanization of the base, a connecting member extending substantially at right angles to said plate outwardly through the bottom layer, an outer plate secured to the lower outer end of said connecting member, and a.

rubber filling compound contained within the openings of said anchor plate andadapted to form connections between said layers upon vulcanization of said base.

4. In rubber foot wear, the combination with the shank provided with an upper layer of rubber compound and a lower layer composed of rubber and fabriea'nd extending over the heel and sole on either side of the shank, a perforated anchor plate horizoncated' betw'een them prior to vulcanization ofth e base, pins'extending from theouter lower. surface of the shank transversely through said lower layer and rigidly united to said anchor plate, an outer wear plate secured to the outer lower ends of said pins, and a rubber filling material insertedin said perforations .and united to said layers by vulcanization.

. KARL F. W. KOCH. Witnesses: V (LA. SoANs,

EMILm Ross.

tally disposedbetween said layers and -lo- 

